Don’t forget some people have antivirus scanners that will load up every link when the email is opened, so you can’t have the link expire after 1 visit. This i

Don’t forget some people have antivirus scanners that will load up every link when the email is opened, so you can’t have the link expire after 1 visit. This is I think why unsubscribe links now have a single button saying “Unsubscribe” or similar when you press them. Likewise anything interesting should require a 2nd user action after loading the page.